The death of Dungeons & Dragons creator Gary Gygax earlier this week was a sad day for everyone who has ever lost themselves in a tabletop role-playing adventure. It's difficult to overstate just how much videogames owe to Gygax's work: Trying to imagine gaming without D&D is like trying to imagine modern civilization without the wheel or electricity. Sure, it could have happened, but it would have turned out radically different. So please observe a moment of silence as we recount the debt that videogaming owes to 1974's pen-and-paper classic.

Gygax designed the original D&D game with Dave Arneson in 1974, and went on to create the Dangerous Journeys and Lejendary Adventure RPGs, as well as a number of board games. He also wrote several fantasy novels. He died Tuesday 4th March, 2008, life rolled him a critical hit on a 69-sided dice.

His legacy lives on in a number of modern game design tenets:

1. Everything can be reduced to numbers

Perhaps D&D's most influential innovation was the notion that everything can be depicted with numbers. Strength and endurance and magic power are just statistics, determined with the roll of the (very fancy) dice. Luck and skill are probabilities, calculated with complex formulae (and more fancy dice). Playing D&D required a good head for arithmetic, or maybe one of those new-fangled pocket calculators, but the payoff was a thoroughly consistent game. When you tried beating up a high-level troll, you could be confident that your death was mandated by math and not just a cranky dungeon master.

And how does this relate to videogames? Hell, how doesn't it? The more complex games become, the more they swipe from D&D's player handbook. Not just RPGs, either, but every genre. Developers now recognize a universal truth: Leveling up is awesome. Racing games do it (Need for Speed). Sports games do it (Superstar Mode in Madden). First-person shooters? Yup -- Call of Duty 4. Platform games? Ever played Castlevania? We're still waiting on a stat-driven version of Tetris, but we're confident that it's merely a matter of time.

2. You're not alone

Like all pre-videogames, D&D was meant to be played with friends. But unlike, say, Monopoly, D&D wasn't made for families to enjoy together -- it was unapologetically designed for geeks. And in 1974, no one did anything for geeks; before computers became a fact of life and the Internet connected people with shared interests regardless of distance, the shy, awkward intellectual was a figure of ridicule rather than a potential Silicon Valley billionaire. D&D was a much-needed alternative to Chess Club.

D&D brought thousands of ostracized geeks together and created a geek culture that became the petri dish in which videogames flourished once the pop novelty of Pong and Pac-Man faded away. Today, videogames are all about hanging out with other geeks who share your taste, whether it's music nuts pretending to be video stars with Rock Band's plastic instruments or horny furries yiffing in Second Life.

3. Players want to own their character

D&D offered "stock" characters, but dedicated players didn't go adventuring with boring pre-defined heroes; they rolled their own. Whether as Th'ugg the Kobold Slayer (he hates dog-men and has the two-handed sword proficiency to back it up) or as Malevola the Chaotic-Evil Seductress (she's ostensibly a mage but seems to invest more skill points in charisma), half the fun of D&D was defining a hero and developing him or her over the course of a few months of questing. You could even draw a portrait in that little box on your character sheet.

Massively multiplayer games are all about custom characters, but even action games are catching on; Drawn to Life basically lets you control a living character sheet doodle. And Mass Effect let players define not only the hero's appearance and gender, but also his (or her) backstory -- no surprise, seeing how its designers at BioWare cut their teeth making D&D games for PC.

4. Emergent gameplay is good gameplay

It's taken three decades, but videogames are finally catching on to one of the most fundamental elements of D&D: emergent gameplay. Because the rules and guidebooks for the tabletop game were merely a suggestion, a set of conditions and constraints for building an adventure, the actual content and outcome of every group and every session varied wildly. This wasn't a matter of the random math, though -- it was the human factor. The dungeon master was a sort of guide, nudging the heroes in the right direction and adapting rapidly when they strayed.

Not surprisingly, videogames have generally kind of sucked at this. The computer serves as a dungeon master by proxy for the creators, and computers aren't known for their boundless imagination. But they're catching up thanks to canny design. MMOs are very much the successors to D&D, bringing people together to deal with the randomness that results from so many real players gathered in a single place (not to mention the occasional interference of the game masters). But even smaller-scale games like Battlefield and Halo 3 have become sandboxes for goofing around, and single-player games like The Sims and Grand Theft Auto give players enough freedom to make their own fun.

5. Good stories compel, poor stories suck

A D&D adventure lived or died by its dungeon master. Those who have quested with a talented DM have wonderful memories of the game, while players whose DMs were human failures simply wonder how anyone could enjoy it. But what makes the difference? Simply put, imagination and a knack for storytelling. D&D was about adventuring and camaraderie, but also about seeing how the story unfolded.

Narrative has developed over the years into a crucial element of videogames. From Prince of Persia's simple pantomime to Hotel Dusk's dialogue-driven noir mystery, story has more or less replaced high scores as the reason to finish a game. A story poorly told can leave players confused or angry -- see forum responses to Halo 3 and Assassin's Creed. Meanwhile, a brilliant story can escalate a good game to greatness. Would players be as enamored of BioShock without its egg-headed tale of free will in an undersea Objectivist paradise gone horribly wrong, a tale whose outcome is affected by player choice? Probably not.

It's still a far cry from a great D&D campaign...but slowly, video games are getting there.